bundles/basic: use metadata.get()

bundles/basic/items.py

@@ -30,7 +30,7 @@ files = {
 }
 
 locale_needs = set()
-for locale in sorted(node.metadata['locale']['installed']):
+for locale in sorted(node.metadata.get('locale/installed')):
     actions[f'ensure_locale_{locale}_is_enabled'] = {
         'command': f"sed -i '/{locale}/s/^# *//g' /etc/locale.gen",
         'unless': f"grep -e '^{locale}' /etc/locale.gen",